
	package com.dr.common;

	import java.math.BigInteger;
	import java.security.MessageDigest;
	import java.security.NoSuchAlgorithmException;

	/**
	 * 使用md5算法，进行加密
	 */
	public class MD5Util {
		public static String md5(String plainText) {
			byte[] secretBytes = null;
			try {
				secretBytes = MessageDigest.getInstance("md5").digest(plainText.getBytes());//每个字符加密后返回
			} catch (NoSuchAlgorithmException e) {
				throw new RuntimeException("没有md5算法");
			}

			String md5code = new BigInteger(1, secretBytes).toString(16);  //（转16进制）

			for (int i = 0; i < 32 - secretBytes.length; i++) {//长度一致32
				md5code = "0" + md5code;
			}
			return md5code;
		}
		
		public static void main(String[] args) {
			System.out.println(md5("helloworld"));
		}
	}


